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<FONT SIZE=1 COLOR=#660033>Microsoft® Visual Basic® Scripting Edition</FONT><BR>
<FONT SIZE=5 COLOR=#660033><B>If...Then...Else Statement</B></FONT>
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<FONT SIZE=2> <A HREF="vbstoc.htm">Language Reference</A> <BR>
<A HREF="vbs16.htm">Version 1</A> <P></FONT>
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<H5>Description</H5>
<BLOCKQUOTE>Conditionally executes a group of statements, depending on the value of an expression.</BLOCKQUOTE>
<H5>Syntax</H5>
<BLOCKQUOTE><b>If</b> <i>condition </i><b>Then</b> <i>statements </i>[<b>Else</b> <i>elsestatements </i>]
<P>Or, you can use the block form syntax:
<P><b>If</b> <i>condition </i><b>Then</b><BR>
[<i>statements</i>]<BR>
[<b>ElseIf</b> <i>condition-n</i> <b>Then</b><BR>
[<i>elseifstatements</i>]] <b>. . .</b><BR>
[<b>Else</b><BR> [<i>elsestatements</i>]]<BR>
<b>End If</b>
<P>The <b>If...Then...Else</b> statement syntax has these parts:<P>
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<TD><FONT SIZE=2><b>Part</b></FONT></TD>
<TD><FONT SIZE=2><b>Description</b></FONT></TD></TR>
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<TD><FONT SIZE=2><i>condition</i></FONT></TD>
<TD><FONT SIZE=2>One or more of the following two types of expressions:<P>A
<A HREF="vbs0.htm#defNumericExpression">numeric</A> or
<A HREF="vbs0.htm#defStringExpression">string expression</A> that evaluates to <b>True</b> or <b>False</b>. If <i>condition</i> is
<A HREF="vbs0.htm#defNull"><B>Null</B></A>, <i>condition</i> is treated as <b>False</b>.<P>
An expression of the form <b>TypeOf</b> <i>objectname</i> <b>Is</b> <i>objecttype</i>. The <i>objectname</i> is any object reference and <i>objecttype</i> is any valid object type. The expression is <b>True</b> if <i>objectname</i> is of the object type specified by <i>objecttype</i>; otherwise it is <b>False</b>.</FONT></TD></TR>
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<TD><FONT SIZE=2><i>statements</i></FONT></TD>
<TD><FONT SIZE=2>One or more statements separated by colons; executed if <i>condition</i> is <b>True</b>.</FONT></TD></TR>
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<TD><FONT SIZE=2><i>condition-n</i></FONT></TD>
<TD><FONT SIZE=2>Same as <i>condition</i>.</FONT></TD></TR>
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<TD><FONT SIZE=2><i>elseifstatements</i></FONT></TD>
<TD><FONT SIZE=2>One or more statements executed if the associated <i>condition-n</i> is <b>True</b>.</FONT></TD></TR>
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<TD><FONT SIZE=2><i>elsestatements</i></FONT></TD>
<TD><FONT SIZE=2>One or more statements executed if no previous <i>condition</i> or <i>condition-n</i> expression is <b>True</b>.</FONT></TD></TR></TABLE></BLOCKQUOTE>
<H5>Remarks</H5>
<BLOCKQUOTE>You can use the single-line form (first syntax) for short, simple tests. However, the block form (second syntax) provides more structure and flexibility than the single-line form and is usually easier to read, maintain, and debug.
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<TD VALIGN=TOP><FONT SIZE=2><b>Note</b> With the single-line syntax, it is possible to have multiple statements executed as the result of an <b>If...Then</b> decision, but they must all be on the same line and separated by colons, as in the following statement:
<BLOCKQUOTE>
<PRE><FONT FACE="Courier New" SIZE=3><FONT COLOR= "#FF0000">If</FONT> A > 10 <FONT COLOR= "#FF0000">Then</FONT> A = A + 1 : B = B + A : C = C + B
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When executing a block <b>If</b> (second syntax), <i>condition </i>is tested. If <i>condition</i> is <b>True</b>, the statements following <b>Then</b> are executed. If <i>condition</i> is <b>False</b>, each <b>ElseIf</b> (if any) is evaluated in turn. When a <b>True</b> condition is found, the statements following the associated <b>Then</b> are executed. If none of the <b>ElseIf</b> statements are <b>True</b> (or there are no <b>ElseIf</b> clauses), the statements following <b>Else</b> are executed. After executing the statements following <b>Then</b> or <b>Else</b>, execution continues with the statement following <b>End If</b>.<P>
The <b>Else</b> and <b>ElseIf</b> clauses are both optional. You can have as many <b>ElseIf</b> statements as you want in a block <b>If</b>, but none can appear after the <b>Else</b> clause. Block <b>If</b> statements can be nested; that is, contained within one another.<P>
What follows the <b>Then</b> keyword is examined to determine whether or not a statement is a block <b>If</b>. If anything other than a comment appears after <b>Then</b> on the same line, the statement is treated as a single-line <b>If</b> statement.<P>
A block <b>If</b> statement must be the first statement on a line. The block <b>If</b> must end with an <b>End If</b> statement.</BLOCKQUOTE>
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